He said: “As CMT progresses, it can start to affect the hands and if I do start to lose the sensation it will probably stop me from playing the viola and potentially the piano.

“However, it also might never happen so I’m not going to worry just now. I try and play as much as I can, while I still reasonably can.”

CMT UK will launch Charcot-Marie-Tooth Awareness Month on Saturday.

This year’s campaign aims to raise awareness of the symptoms among people who have not been diagnosed and also make doctors more aware of the condition.

Mr McLennan, who lives with his wife Claire and daughter Ophelia, two, said: “I have made my peace that I won’t ever run properly and that I may need walking aids when I am older, and that I may not be able to play my instruments as long as I would want, but that’s my lot in life and I’m happy.

“I just remain positive and thankful that in terms of severity, my CMT is pretty mild.”